Absorbent articles are well known in the art. These articles typically have an absorbent assembly held or positioned in proximity to the body of a wearer during use in order to capture and absorb bodily exudates discharged from the wearer. Typical absorbent articles include a topsheet facing the wearer, which permits fluid exudates to pass through, and an outer cover, which:prevents the exudates from escaping from the absorbent article.
The toilet training stage may be referred to as the “point of exit” from the diaper product category because toddlers who have successfully completed toilet training typically no longer wear diapers. The age at which children are toilet trained in “developed” countries has increased steadily over the past several decades and is now in the range of about 24-48 months. One reason for which toilet training has become delayed is that significant technical improvements have been made in diaper dryness and comfort. For example, when wearing a typical modem diaper, the child may have dry skin even after one or more occurrences of urination. As a result, the child may feel little or no discomfort and often may not even be aware that he or she has urinated.
Some parents may have the child wear cotton training pants or cotton underwear during urinary training so the child feels discomfort following urination in his or her “pants.” It is believed that such discomfort assists with learning or provides motivation to learn to voluntarily retain urine (at least until the child can urinate in a socially acceptable time/location). Cloth training pants leave the skin wet and, due to their high breathability, promote evaporative cooling of the skin, further enhancing discomfort. The current tradeoff in this approach, however, is that cloth training pants have poor urine containment, often leading to wet clothing and wet surroundings, e.g., carpeting, furniture, etc. There is a need to provide disposable absorbent articles where the article itself has features which facilitate toilet training without compromising the convenience of the disposable product form.
Several attempts have been made in the prior art to provide disposable absorbent articles which provide some sort of feedback such as a “coolness” or “wetness” signal to alert the wearer of the incidence of urination. Examples of such approaches have included garments which provide a “feel wet” signal. U.S. Pat. No. 6,958,432 discloses an example of a garment with a member which attempts to provide such a feeling of wetness. U.S. Pat. No. 6,642,427 discloses a garment which contains endothermic salts and similar substances to provide a temperature change or feeling of coolness. U.S. Pat. No. 5,797,892 discloses an article which attempts to change size or shape upon urination to provide a tactile feedback to the wearer upon urination.
These approaches found in the prior art have met with some commercial success and accomplish the training objective at least to some degree. It has been found during development of the present invention that several—sometimes contradictory—characteristics of feedback mechanisms are important. For example, it has been found during development of the present invention that an ideal feedback mechanism should provide a nearly immediate response upon urination. If the response time for the signal is too long, the child may not properly associate the signal with the urination event which triggered it. It has also been found during development of the present invention that the feedback mechanism should ideally also provide a temporary signal. The temporary duration of the signal helps to reinforce the association with the urination event. In other words, if the signal lasts too long or indefinitely the wearer may become undesirably accustomed to the signal. Additionally, a signal which persists may lead to undesirable impacts such as stress on the wearer's skin.
Another characteristic of well designed feedback mechanisms discovered during development of the present invention is that such mechanisms should be harmless to the wearer and the wearer's skin. For example, a feedback mechanism which provided prolonged contact of a urine saturated component with the skin could lead to skin irritation and, therefore, would not be ideal.
It has also been found during development of the present invention that ideal feedback mechanisms be unmistakable to the wearer. For example, if the signal provided to the wearer were too subtle or ambiguous the training benefit of the signal may not be effectively achieved.
Consequently, a need, therefore, exists for disposable absorbent articles and garments which provide urination feedback mechanisms which are as immediate and unmistakable to the wearer as possible. Such feedback mechanisms should also be temporary and harmless. It would desirable to provide an article that can facilitate urinary toilet training by enhancing a wearer's awareness that urination has occurred by providing such a signal to the wearer while at the same time providing the protection of an absorbent article to prevent soiling of the wearer's clothing and surroundings.